Porous Transport\nLayers with Laser Micropatterning\nfor Enhanced Mass Transport in PEM Water Electrolyzers

Efficient electrochemical energy conversion technologies,\nsuch\nas fuel cells and water electrolyzers, require high current densities\nto lower the capital cost for large-scale commercialization but are\noften limited by mass transport. In this study, we demonstrated exceptional\nelectrochemical performances in proton electrolyte membrane water\nelectrolyzers (PEMWEs) creating micropatterned pore channels in the\nporous transport layer (MPC PTL) using a picosecond laser. This approach\nyielded an impressive performance of 1.82 V @ 2 A·cm<sup>–2</sup>, which is better than commercial PTL of 1.90 V @ 2 A cm<sup>–2</sup>. The significant performance enhancement is attributed to the micropatterned\nporous channel structure, facilitating the efficient expulsion of\noxygen bubbles and input of reactant water. This work provides valuable\ninsights for the design of PTL responsible for biphasic transport\nin electrochemical energy conversion technologies.